Making the transition from silver to gold is always difficult because
of the extreme difference in the way the two metals conduct heat � and
it’s compounded when you’re trying to solder one to the other.

Silver is a great conductor of heat, which explains why you need to
heat the whole object. Apply heat to just one point on a sheet of
silver and it will radiate out to the edges; you need to keep the
torch moving to bring the whole thing up to temperature before solder
will flow.

Gold, on the other hand, is a poor heat conductor. Apply heat to one
point on a sheet of gold and you’ll burn a hole in the sheet before
the edges get anywhere close to the same temperature. The ability to
"spot solder" gold � i.e., heat only the spot you’re working on � is
what makes it such a joy to use, especially when you’re working on a
small scale. It also makes it very easy to melt!

You can, however, successfully solder a gold bezel to silver sheet
without melting the gold. The most surefire way is to heat from
below. Place the silver on steel mesh which rests on a tripod. (You
can make your own setup or buy one from your favorite supplier.) Keep
in mind that the screen will act as a heat sink, necessitating a
hotter/bigger torch flame than otherwise.

If you prefer to heat from above, you’ll have greater success if you
remember to keep the flame off of the bezel at all times! Heat
around the outside of the bezel and then move the flame inside,
raising it slightly as you pass over the bezel, and then back to the
outside, again raising it as you move over the bezel. It will take
some practice, but it works. It will also help to solder on a surface
that absorbs heat, like charcoal; the silver will get up to
temperature faster. And, finally, consider 18k or 22k bezel wire; the
melting temperatures are higher ( and the color contrast with the
silver greater).